I know of the conceptualized "Sinkers", "Floaters" and "Hunters" that Carl Sagan and Edwin Salpeter of Cornell conceived of - as possible life forms that might inhabit a gas giant. At the time they conceived of this, there was no real info about the amount of amino acids that might exist in the atmospheres of planets like Saturn and Jupiter. We have also learned a lot more about the composition of these planets. I am wondering if these life form ideas are still possible alien life forms that could develop in a gas giant of some type.
Based on the temperatures and composition of Sudarsky class II planets - which are closer in to the star. Supposedly temperatures become too warm for ammonia ice to be stable. Instead, Class II gas giants have clouds of water vapor, giving them a high albedo and a beautiful blue-white coloration.
Would the possibility of life of some kind be able to develop there and thrive? Would it mostly be microbial if anything? Would larger multicellular beings be possible in the forms Sagan and Salpeter dreamed of or some other form? Would it have to be Anaerobic? Could it have developed on a more terrestrial form of the planet before it grew to a gas giant?
I am curious about the possibilities of this for a story, but I want to make it at least believable even if it is just an unlikely chance of a life form of a kind we might not even recognize as life as we define it.